Table 1. Patient characteristics.

Characteristics	n	%a
Total	447	100
Sex
Male	370	82.8
Female	77	17.2
Smoking history
Never	40	8.9
Former	238	53.2
Current	161	36.0
Unknown	8	1.8
Histology
Adenocarcinoma	244	54.6
SCC	138	30.9
Other	65	14.5
Stage
I	166	37.1
II	99	22.1
III	146	32.7
IV	36	8.1
Grade
I	32	7.2
II	255	57.0
III	158	35.3
Not reported	2	0.4

^apercentages have been rounded and may not total 100%.

Abbreviation: SCC = squamous cell carcinoma.